1. Announcements Homework for tomorrow…
Ch. 29: CQ 10, Probs. 20, 22, & 54
CQ4a) E1 = E2 = -(10 V/m) ihat b) E1 = -(5 V/m) ihat, E2 = -(20 V/m) ihat
CQ5: accelerates right
29.6: W = 1.6 x J
29.12: Ex(0cm<x<2cm) = +2,500 V/m Ex(2cm<x<3cm) = -10,000 V/m
29.44: E = 40 V/m, θ = 27° ccw from +x-axis
Office hours…
MW am
TR am
F 12-1 pm
Tutorial Learning Center (TLC) hours:
MTWR 8-6 pm
F 8-11 am, 2-5 pm
Su 1-5 pm

2. Potential & Field (Combinations of Capacitors)
Chapter 29
Potential & Field
(Combinations of Capacitors)

3. Review… Kirchoff’s Loop Rule… Conductors in Electrostatic Equilibrium…
Capacitance…

4. Combinations of Capacitors
Consider two capacitors in parallel…
Can we find an equivalent capacitor, Ceq, to the two capacitors, C1 & C2? + - + -
Ceq C1 C2

5. Combinations of Capacitors
Consider two capacitors in parallel…
Can we find an equivalent capacitor, Ceq, to the two capacitors, C1 & C2?
YES! + - + -
Ceq C1 C2

6. Combinations of Capacitors
What about for several capacitors in parallel?
Can we find an equivalent capacitor, Ceq, to the capacitors, C1 , C2, … (all in parallel)? + - + -
Ceq C1 C2 C3

7. Combinations of Capacitors
What about for several capacitors in parallel?
Can we find an equivalent capacitor, Ceq, to the capacitors, C1 , C2, … (all in parallel)? + - + -
Ceq C1 C2 C3

8. Combinations of Capacitors
Consider two capacitors in series…
Can we find an equivalent capacitor, Ceq, to the two capacitors, C1 & C2? + - + - C1
Ceq C2

9. Combinations of Capacitors
Consider two capacitors in series…
Can we find an equivalent capacitor, Ceq, to the two capacitors, C1 & C2?
YES! + - + - C1
Ceq C2

10. Combinations of Capacitors
What about several capacitors in series?
Can we find an equivalent capacitor, Ceq, to the capacitors, C1 , C2 ,… (all in series)? + - C1 + -
Ceq C2 C3

11. Combinations of Capacitors
What about several capacitors in series?
Can we find an equivalent capacitor, Ceq, to the capacitors, C1 , C2 ,… (all in series)? + - C1 + -
Ceq C2 C3

12. Quiz Question 1 The equivalent capacitance is 9 F. 6 F. 3 F. 2 F.

13. i.e. 29.7: A Capacitor Circuit
Find the charge on and the potential difference across each of the three capacitors in the figure below.
Given: E = 12 V, C1 = 3 μF, C2 = 5 μF , C3 = 1 μF C1 + - C2 C3